<!DOCTYPE html>
<html>
	<head>
		<meta charset="utf-8">
		<title>背景大小</title>
		<style>
			div#d1{
				height: 600px;
				width: 1500px;
				background-color: darkgrey;
				background-image: url(../image/banner.png);
				background-repeat: no-repeat;
				background-size: cover;
				/* background-size: contain; */
			}
		</style>
	</head>
	<body>
		<div id="d1">
			We change lives
		</div>
	</body>
</html>